Dental implant

ABSTRACT

The invention provides dental implants for fixed and removable prosthetic devices, and has application to single tooth replacement, e.g., caps and crowns, and multiple tooth replacement using one or more implants, e.g., bridges, and multiple implants for full and partial prosthetic devices. Dental implants according to embodiments of the invention comprise a post or posts inserted into the jawbone and a stabilizer that is loaded, in the general area of the gum line, against the jawbone using the post or posts. The stabilizer is secured to each post, loaded against the jawbone, by a fastener system, e.g., a nut threaded to each post.

BACKGROUND OF THE INVENTION

The invention disclosed herein relates generally to dental implants forfixed and removable prosthetic devices and to fixed and removableprosthetic devices including such implants.

Implant dentistry dates back at least to the 1970s. See, e.g.,Principles and Practice of Implant Dentistry, by Charles M. Weiss andAdam Weiss, Mosby Inc., 2001.

SUMMARY OF THE INVENTION

The invention provides dental implants for fixed and removableprosthetic devices and to fixed and removable prosthetic devicesincluding such implants, and has application to, but is not limited to,one or more of the following: single tooth replacement, e.g., caps andcrowns; multiple tooth replacement using one or more implants, e.g.,bridges; and multiple implants for full and partial prosthetic devices.Embodiments of dental implants incorporating the invention may beinstalled in single or multiple root teeth locations.

Dental implants according to embodiments of the invention comprise apost or posts inserted into the jawbone extending therefrom towards theopposing jawbone, and a stabilizer that is loaded, in the general areaof the gum line, against the jawbone, directly or indirectly through gumtissue, using the post or posts. The term loaded or loadable against thejawbone is meant in a broad sense and encompasses loading of thestabilizer against the jawbone in direct contact therewith or throughgum tissue. According to some embodiments, the stabilizer is loadedagainst the jawbone by a force or forces derived from anchoring of thepost or posts in the jawbone. For example, the stabilizer may be urgedin compression against the jawbone via a tensile force applied to thepost or posts. Implants according to the embodiments of the inventionincorporating such stabilizers provide sufficient supporting surfacearea for a prosthetic device even where the size of the post(s) isrelatively small, e.g., typically smaller than that of a post previouslyused for an implant at a particular implant location.

According to some embodiments, the stabilizer is configured to fitsnugly into the implant location at the gum line, so as to be loadableagainst the jawbone. For example, the stabilizer is configured to fit ina space or cavity at the concerned implant location in the mouth,created by the absence of a tooth, or otherwise, loaded against thejawbone at the gum line. The term implant location is meant in a broadsense and corresponds at least generally to the location of a toothformerly in the mouth. For example, the implant may be centered more orless in the location formerly occupied by a tooth, although the implantlocation may be offset from the center of the location of a toothformerly in the mouth, e.g., where the space or cavity formerly occupiedby the tooth is large or the implant is to be inserted where two or moreadjacent teeth were formerly in the mouth.

Various configurations of stabilizers may be used, and the particularconfiguration corresponds generally to a cross-sectional slice of thetooth formerly at the implant location, e.g., such that the stabilizeroccupies a substantial surface area, e.g., all or most of the surfacearea, occupied by the tooth at the gum line at the implant location. Thesurface area of the stabilizer is approximately that of the space orcavity at the gum line, i.e., the surface area of the tooth formerly atthe implant location at the gum line. The thickness of the stabilizer issufficient to withstand the compressive force(s) loading the stabilizeragainst the jawbone and to stabilize a prosthetic device attached to theimplant. Also, according to some embodiments of the invention, theprosthesis extends over the stabilizer, which should have sufficientthickness to permit this.

In the illustrated embodiments, the stabilizer comprises a platform thatincludes opposed parallel major sides and at least one minor sidetransverse to the major sides, e.g., may have a generally solidrectangular configuration. The platform may be rectangular ortrapezoidal in cross section, or may have other cross-sectional shapes.

According to some embodiments of the invention, the stabilizer issecured to the post, loaded against the jawbone, by a fastener system.In one embodiment, the platform includes a hole for each post, and arespective post is received in a respective hole and attached to theplatform by the fastener system.

A dental implant according to some embodiments of the inventioncomprises at least one post which is inserted into a patient's jawboneextending towards the opposing jawbone and a stabilizer including amajor side and a hole in the major side for each post of the dentalimplant. The relative sizes of each post and the stabilizer are suchthat a transverse dimension of the major side of a stabilizer issubstantially larger than a largest transverse dimension, e.g., adiameter, of any of the posts at the location at which the particularpost passes through a hole. Each hole and a portion of a correspondingpost which in use would be received in a hole comprise complementaryconfigurations. The configuration of a respective hole and theconfiguration of a respective post preferably provides but does not haveto provide a snug fit, e.g., a tight or interference fit. The implantalso includes a fastener system which, in use of the dental implant,secures the platform to at least one post loaded against the jawbone.

Any suitable post and any suitable insertion methodology may be used.For example, in the illustrated embodiments, each post includes a screwthread extending along at least the portion of the post which is to bethreaded into the jawbone. In some embodiments, the threaded portion iscircular in cross section, and the post diameter may be tapered. Inthese embodiments, each post is secured to the jawbone at least usingthe screw thread thereof with a free end of the respective postextending from the jawbone, and the stabilizer is positioned to receivea respective post in a respective hole with the major side of thestabilizer extending transverse to an axis of the post. In theseembodiments. The free end of at least one post extends beyond the majorside of the stabilizer and the at least one post and the stabilizer aresecured by the fastener system and a portion or portions of the dentalimplant extend beyond the major surface of the platform as to be able toreceive a prosthetic device.

In some embodiments, as mentioned above, the stabilizer comprises aplatform including opposed parallel major sides and at least one minorside, where the at least one hole extends through the major sides. Inthe installed condition of the implant, the at least one post passesthrough the at least one hole with its free end extending beyond anadjacent major side of the platform.

In some embodiments, the implant includes at least one anchor which isattached to the implant projecting from the stabilizer or platform andadapted to assist in securing a prosthetic device to the dental implant.

Dental implants according to some embodiments of the invention may beinstalled at locations formerly occupied by teeth having one root or aplurality of roots. Generally, a post is inserted for each root at thatlocation, and the platform has a hole for each post.

A method according to an embodiment of the invention for installing adental implant of the type disclosed herein comprises providing a holein a jawbone for each post of the implant positioned to be alignablewith each hole in a stabilizer, installing the stabilizer with a freeend of a respective post extending from a respective jawbone hole towardthe opposing jawbone a distance sufficient to enter a respective hole inthe stabilizer while the stabilizer contacts the jawbone or gum tissueadjacent thereto at the gum line. In an embodiment in which thestabilizer is to be installed in direct contact with the jawbone, thegum at the gum line is cut away to expose the jawbone and provide accessthereto for the stabilizer to directly contact the jawbone. Thestabilizer is mounted with each post received in a respective hole inthe stabilizer and the stabilizer in contact with jawbone at the gumline (or gum tissue adjacent thereto), and the stabilizer is attached tothe at least one post with the stabilizer loaded against the jawbone,e.g., by a fastener system.

According to some embodiments, the fastener system used to attach thestabilizer to the at least one post, includes a threaded nut for eachpost and a correspondingly threaded portion of the respective post.

BRIEF DESCRIPTION OF DRAWINGS

The invention is illustrated in the figures of the accompanyingdrawings, which are meant to be exemplary and not limiting, and in whichlike references are intended to refer to like or corresponding parts.

FIG. 1 is an exploded perspective view of a dental implant according toan embodiment of the invention.

FIG. 2 is an exploded perspective view of a dental implant according toanother embodiment of the invention.

FIG. 3 is a diagram showing in perspective an inserted dental implant ofthe type depicted in FIG. 1 and an installed dental prosthetic device (acap) according to an embodiment of the invention, and also teeth next tothe implant.

FIG. 4 is a partial cross-sectional view from the side of the inserteddental implant and installed dental prosthetic device depicted in FIG.3.

FIG. 5 is a diagram showing in perspective an inserted dental implantand an installed dental prosthetic device according to an embodiment ofthe invention, and also teeth next to the implant.

FIG. 6 is a partial cross-sectional view from the side of the inserteddental implant and installed dental prosthetic device depicted in FIG.5.

FIG. 7 is a diagram similar to that of FIG. 5 showing in perspective twoinserted dental implants and an installed dental prosthetic device (abridge) according to another embodiment of the invention.

FIG. 8 is a diagram showing a front view of four inserted dentalimplants and an installed dental prosthetic device for the four lowerincisor teeth locations and the two lower canine teeth locationsaccording to an embodiment of the invention.

FIG. 9 is a diagram showing a front view of six inserted dental implantsand an installed dental prosthetic device for the four lower incisorteeth locations and the two lower canine teeth locations according to anembodiment of the invention.

FIG. 10 is an exploded perspective view of a dental implant for aremovable prosthetic device according to an embodiment of the invention.

The embodiment of the dental implant 10 depicted in FIG. 1 and theembodiment of the dental implant 10 a depicted in FIG. 2 each compriseat least one post 12, and at least one stabilizer 14.

The stabilizer 14 may be is configured as described above and in someembodiments includes opposed major sides and at least one minor side. Inthe illustrated embodiments, the stabilizer comprises a platform 14,where the opposed major sides 15 are parallel and the at least one minorside 17 is transverse, e.g., generally normal, to the major sides. Otherconfigurations and shapes may be used. For example, the major sides maybe generally parallel or sloped relative to each other, or includemultiple portions which intersect at a vertex or vertices, and the minorsides may not be parallel, but sloped relative to each other, or includemultiple portions which intersect at a vertex or vertices. As a generalmatter, the stabilizer may be of generally solid rectangular ortrapezoidal (e.g., see FIG. 4) configuration. The platform is generallyplate-like or disc-like where the thickness is substantially less thanthe area of either major side. Depending upon the location of theimplant, a stabilizer can have a perimeter or circumference of about 8mm to about 25 mm. Also depending upon location, the stabilizer can havea thickness of about 2 mm to about 4 mm, with about 3 mm to 4 mm beingpreferred.

A fastener system referenced generally by 16 is associated with a postor posts 12. Each of the platforms 14 includes a through hole 18 for arespective post 12. The respective hole 18 and an intermediate portion20 of each post 12 between the upper end 22 and the lower end 24 therespective post where the respective post passes through the respectivehole in the inserted condition of the respective implant (see FIGS. 4and 6) are complimentarily configured, where the size of the respectivehole is slightly larger than the size of the respective post portion toprovide a snug fit of the respective post in the respective hole. Insome embodiments, the hole or holes 18 in the platform are not threaded.In such embodiments, the intermediate portion 20 of the post may or maynot be threaded. Either or both the upper portion 26 and the lowerportion 28 of the respective posts 12 are configured to allow therespective post to be passed through the respective hole duringinsertion of the particular implant. As discussed below, many postconfigurations other than those illustrated in FIGS. 1 and 2 may beused.

As discussed in more detail below, in the inserted condition of theimplant 10, the platform 14 rests on or otherwise contacts and is loadedagainst the jawbone 34 at the gun line 36 (see FIGS. 4 and 6). When theplatform is loaded against the jawbone through gum tissue, it ispreferred that the gum tissue should not be soft tissue. Forcing theplatform directly against the jawbone puts pressure on the bone, whichmaintains bone structure and avoids or reduces drift of the implant.This arrangement can prevent or reduce growth of soft tissue between theplatform and the bone, which could otherwise lead to irritation orand/or bleeding, and can also promote gingival health.

In the illustrated embodiments, each of the posts 12 includes a thread30 that extends at least along the lower portion 28 of the respectivepost, but may extend in other portions of the post (or additionalthreads may be provided) depending upon the fastener system 16 to beused and the configurations of the respective hole 18 and postintermediate portion 20. If the selected fastener system 16 includesthreads on the upper portion 26 of the post, such threads may beseparate from or related to (e.g., a continuation) of thread 30. In theembodiments depicted in FIGS. 1 and 2, the fastener system 16 comprisesa nut 38 that is threaded to the upper portion 26 of the post. Althougha pre-threaded system is preferred, in some embodiments, a selfthreading system may be used, e.g., either the post upper portion 26 orthe nut 38 are not threaded and threads are created when the nut is“threaded” to the post upper portion. The fastener system 16 may includea counter-rotation feature to resist loosening, e.g., a lock washer 40,or a retention nut, or double nut (not shown).

For use with fixed prosthetic devices, a core 42 (see FIGS. 3 and 4) isbuilt up surrounding the nut to accept the fixed dental prostheticdevice, as described in more detail below, and can also hold the nut inplace. Embodiments of the implant 10 may also include one or moreanchors 48 used to assist in securing a fixed prosthetic device to theimplant 10. Anchors 48 may be configured and attached to the implant 10in any suitable manner. In the particular embodiment illustrated inFIGS. 1 and 2, an anchor 48 comprises one or more posts attached to orforming part of the platform 14. A post 48 may be attached to theplatform 14 extending from the top surface thereof or at an edge, andmay extend normal to the top surface of the of the platform or at anangle thereto. For example, a post extending from or adjacent an edgemay be angled to extend inwardly relative to the platform, and a postextending close to an edge of the nut 38 may be angled to extendoutwardly relative to the platform. As depicted in FIGS. 3 and 4, a postor posts 48 extend so that they can be embedded in the core 42 andpossibly also in dental cement used to secure a prosthetic device to theimplant.

The anchor may be attached to the platform in any suitable manner, e.g.,by means of threads, suitable bonding technologies, e.g., adhesives orcements, ultrasonic, soldering, or welding, etc. For example, an endpart may be inserted into a blind or through hole in the platform andattached as just described or by other suitable methods. A platform 14may be formed with one or more posts 48 extending therefrom by anysuitable technology, e.g., stamping, milling, casting or otherwisemolding, etc.

In another embodiment, an anchor includes a base portion and a tabportion extending at an angle from the base portion. The base portionincludes a hole therethrough and is mounted in the implant on theplatform 14 with the upper portion of the post 12 passing through thehole, with the tab portion extending upwardly with at least a portionthereof exposed so it can be embedded at least in the core 42 andpossibly also in a dental cement used to secure a prosthetic device tothe implant. For example, for an anchor 48 having a base portion thatextends beyond the outer periphery of the nut, the angle at which thetab extends from the base can be about 90°, but can be any suitableangle that provides for the tab to extend above the platform spaced fromthe nut and/or the post sufficiently to be embedded in the core andpossibly in the dental cement used to secure a prosthesis to theimplant. For example, for a base portion that extends just slightlybeyond the outer periphery of the nut, the angle may be larger that 90°to provide clearance between the nut and the anchor tab.

Anchors may be made of any suitable material, e.g., the same material asthe platform.

The sizes and configurations of the dental implants 10, 10 a illustratedin FIGS. 1-7 may vary depending upon, e.g., the tooth position in whichthe particular implant is inserted. Generally, the upper portion 26 andintermediate portion 20 of the posts 12 are tubular and the diameter ofthe post decreases or tapers from the intermediate portion 20 to thelower end 24 of the post, e.g., the lower portion 28 is generallyfrustoconical. The entire post may be threaded or only portions thereof,as discussed above. For example, the upper portion of a post may betubular and threaded (where the fastener system includes a threadednut), the intermediate portion may be tubular or of rectangular or othercross sectional shape and need not be threaded, and the lower portionmay be tubular or generally conical or frustoconical and threaded. Insome embodiments, the post 12 may include stepped portions, or may besplined or splintered, or include structure other than or in addition toa thread to secure the post to the bone. For example, a post may bepress-fitted to the jawbone rather than threaded. Many suitable postconfigurations other that those illustrated may be used and will be knowto those working in this field.

The configuration, e.g., size (diameter and length) and shape of theparticular post may vary as discussed above depending upon the toothposition at which the post will be implanted, characteristics of theparticular patient, and other factors which may arise on animplant-by-implant and patient-by-patient basis. Generally, as discussedabove, a post is implanted for each root of the tooth at the position inwhich the implant will be implanted, e.g., one post for the incisor andcanine tooth positions and two or three posts for the molar toothpositions.

However, in the embodiment depicted in FIGS. 1-3, the entire post isthreaded, with the upper and intermediate portions being tubular and thelower portion being generally frustoconical.

The posts 12 generally are made of a non-corrosive material or materialsand have a high tensile strength. For example, a titanium post issuitable. The posts may be coated as known in the art, for betteradhesion to bone. The posts have lengths of from about 18 mm to about 30mm and outer diameters of from about 1 mm to about 4 mm. The diameter ofmost posts falls in the general range of from about 1.6 mm to about 3.7mm, with about 2.2 mm being a likely mean. The particular length anddiameter depends on a number of factors such as tooth position andpatient conditions. The length of the post inserted into the jawbone canbe about 10 mm to about 20 mm, and the length protruding from thejawbone can be about 8 mm to about 10 mm, part of which, e.g., about 3mm to about 4 mm, passes through the platform and the remainderextending beyond the platform. The size of the nut (OD) can be about ¼to about ½ the size of the platform (a cross dimension, e.g., diameterof the platform). The lower portions of the posts have thread sizespreviously used for dental implant posts, and the upper portions havethe same or similar threads. The nuts have threads that mate with thoseon the upper portion of the posts.

The platform is similarly made of a non-corrosive material or materials,e.g., stainless steel, a gold alloy, titanium. The size of the platformdepends upon tooth position and/or patient characteristics, amongpossible other things. For example, a platform for a particular toothlocation is shaped so as not to interfere with any adjacent teeth.Suitable platform sizes include: for incisor teeth positions, a surfacearea that can be in the general range of from about 4 mm to about 6 mm;and for molar teeth positions, a surface area (e.g., upper majorsurface) that can be in the general range of from about 16 mm to about22 mm. The platforms generally are shaped as described above. Asmentioned above, the thickness of the platform can be from about 2 mm toabout 4 mm, and the perimeter or circumference from about 8 mm to about25 mm.

FIGS. 3-7 illustrate examples of inserted dental implants with installedprosthetic devices. Methods of inserting the dental implants will bediscussed below in connection with FIGS. 1-7.

For example, FIG. 3 illustrates a dental implant 10 of the type depictedin FIG. 1 implanted in the upper left, second incisor tooth position.For context, an outline of the second incisor tooth is illustrated inFIG. 3 by broken lines, and the canine and First molar teeth are alsoshown. The implant 10 depicted in FIGS. 1 and 3-4 is inserted asfollows. A topical or local anesthetic is applied. (In most cases, thepatient will not need full anesthesia, i.e., will not need to be putasleep.) The platform rests on and is loaded against the jawbone 34 atthe gum line 36, as discussed above. In cases where direct contact isdesired, the gum tissue (e.g., 3 mm-4 mm in thickness) is cut away atthe gum line 36 where the platform would otherwise contact the gum. Agum line cut for the platform may be made before or after the post isinserted. One way to locate the portion of the gum to be cut away is toplace the platform in the position in which it would be installed andpunch the platform against the gum to create a cut in the gum. In caseswhere the platform is to be loaded against the jawbone through gumtissue, the presence of soft tissue at the gum line may indicate theneed for a gum line cut or other procedure.

The location of the hole 56 (FIGS. 3-4) in the jawbone 34 for the postis determined depending upon, for example, tooth position and patientcharacteristics and generally corresponds to the root location at theparticular tooth position. An MRI can assist in determining the locationof the hole for the post. A pilot hole (not shown) (e.g., 3 mm deep) isdrilled in the jawbone 34 in conventional fashion to accept theparticular post 12 to be used. A template or guide stent (not shown) maybe used to drill the pilot hole. The actual jawbone hole 56 is thendrilled. In some embodiments of the invention, a self-threading systemis used, i.e., the jawbone hole 56 is not threaded and a thread iscreated in the hole when the post 12 is tightened into the hole.Regardless of whether the hole 56 is self-threaded or not, its diameteris slightly less that the OD of the post (including threads). If thejawbone hole 56 is not self-threaded, then the hole is tapped to matchthe screw thread 30 of the post. The post 12 is threaded to the jawbonehole 56 in conventional fashion. As mentioned above, other types ofposts may be used, and the insertion procedure depends at least to someextent on the particular post used.

Known wrench systems may be used to tighten a post to the jawbone. Forexample, a post may first be hand tightened into the jawbone hole, thenwrench tightened with two or more wrenches ending with the use of atorque wrench. For example, a hand finger wrench may be used, followedby a wing nut wrench, followed by a 30 Newton torque wrench.

The platform 14 is then inserted onto the post 12. For example, theplatform 14 is positioned over the post 12 with the post and the hole 18in the platform 14 aligned and the platform raised (lowered forimplantation in the lower jaw) until it abuts the jawbone 34 at the gumline 36. The platform 14 is positioned so that its upper major surface15 is level with a line or plane at the concerned tooth position. Theimplant may include one or more anchors 48 extending above the platform14.

The fastener system 16 then secures the platform 14 to the post with theplatform loaded against the jawbone. As mentioned above, the fastenersystem 16 used for the implant embodiments depicted in FIGS. 1 and 2comprises a nut 38 threaded onto the upper portion 26 of the particularpost 12. After the lock washer 40 has been seated on the post 12, thenut 38 is initially loosely threaded to the post upper portion 26 untilthe platform is seated against the jawbone. The nut is torqued to apredetermined tension, e.g., 35 Newtons, using a conventional torquewrench to load the platform against the exposed jawbone. Differentwrenches may be used to tighten the nut to the post before using thetorque wrench to tighten the nut to the predetermined tension.

For the embodiments depicted in FIGS. 1, 2, 3 and 4, the core 42 isapplied over the nut 38 and the anchors 48. As illustrated in FIG. 4,the core completely covers the nut and the anchors. However, part of thenut and/or the anchors and/or the top portion of the post may remainexposed to be embedded in a dental cement used to secure a prostheticdevice to the implant. The core 42 may be built-up using glass polymer,silicon beads, resin, composite and/or metal, or any other suitablematerial or materials. This may be done manually or the core can bepre-formed and installed as a prefabricated core, which can includepre-drilled holes for the nut and the anchors. A prefabricated core iscemented to the nut and anchors. Use of a prefabricated core facilitatesinstallation, particularly in the back of the mouth. The installed coreis sized to leave space to be filled by a dental cement to attach aprosthetic device to the implant. In one embodiment, the core can beprovided with a taper (as illustrated), e.g., 7°, to provide spacebetween the core and the interior of the prosthetic device to applycement. The outer surface of the core 42 may be grooved to promoteadherence thereto of the cement.

The foregoing implantation procedures may be carried out during a singlevisit or multiple visits depending primarily upon site preparationrequirements, e.g., whether a tooth extraction is involved. In mostinstances, the procedure can be performed in a single visit, even wherea tooth is extracted during that visit. At the same that the implant isinstalled, or in a subsequent visit, preparation is made to mount adental prosthetic device 66 to the implant. The prosthetic device 66 forimplant 10 may be a cap 66 a (FIGS. 3-4), or a crown 66 b (FIGS. 5-6)for implant 10 a replacing a single tooth, or a bridge 66 c (FIG. 7)anchored to one dental implants 10 a and either an existing tooth oranother dental implant 10 a and bridging one or more teeth positions, orfixed partial (or full) prosthetic device 66 d-e (FIGS. 8-9) to beanchored to two or more implants 10 or 10 a or at least one implant 10or 10 a and at least one existing tooth. The prosthetic devices 66 areotherwise conventional and may be made conventionally.

Preparation to mount a dental prosthetic device includes obtainingimpressions in conventional fashion and providing them to the prosthesismanufacturer. The prosthetic device is typically custom made to fit themouth and may involve milling for an exact fit. With respect to a cap 66a for the second incisor tooth position embodiment illustrated in FIGS.3 and 4, the cap 66 a is seated on the platform 14 extending over theminor sides 17 down past the gum line 36. Therefore, the impressions forthe cap 66 a are taken down to the gum line 36 past the platform sides17 of the platform 14.

In some instances, an impression can be taken and the prosthetic devicemade prior to installation of the dental implant. In such cases, thedental implant and the appropriate prosthetic device can be installed inthe same visit. In cases where the prosthetic device is to be installedin a visit subsequent to installation of the implant, a temporaryprosthetic device (e.g., a conventional temporary cap, not shown, but inconfiguration similar to cap 66 a) may be installed using a temporarycement. As for a permanent installation described below, the cementfills all of the interior of the cap and embeds the core 42 and anyexposed portion of the anchors 48, the nut 38 and the upper post portion26 to temporarily secure the temporary cap to the dental implant 10.

When the permanent cap 66 a is ready, the temporary cap is removed ifone has been installed, any needed preparation is performed, the cap 66a is tested for fit and any adjustments are made, etc., before finalinstallation. The cap 66 a is then installed using permanent cementwhich fills all of the interior of the cap 66 a, and embeds the core 42and any exposed portion of the anchors 48, the nut 38 and the upper postportion 26 to permanently secure the cap to the dental implant 10.Installation includes proper seating and positioning of the cap 66 aover the platform 14 and against the jawbone 34, etc., as depicted inFIGS. 3 and 4.

The dental implant 10 a illustrated in FIGS. 2 and 5-6 includes threeposts 12 and is implanted in a molar tooth position. The descriptionabove for the single post implant 10 of FIGS. 1 and 3-4 generallyapplies to the multi-post implant 10 a of FIGS. 2 and 5-6, including thediscussions relating to posts, platforms and fasteners systems, exceptthat post and platform sizes may differ and the platform 14 has a hole18 for each post. Thus, the description above applies generally to posts12, platform 14, nuts 38 and anchors 48 of the embodiment of FIGS. 2 and5-6.

The insertion procedure for the multi-post implant 10 a is also similarto that for the single post implant 10. After site preparation,generally as described above, a hole 56 is drilled in the jawbone 38 inconventional fashion to accept each of the particular posts 12 used. Thepositions of the holes 56 correspond generally to the root positions atthe tooth location, and are selected based on site conditions.

After the posts have been inserted, the platform 14 is inserted onto theposts 12, e.g., by positioning the platform 14 over the posts 12 withthe posts and the holes 18 in the platform 14 aligned and the platformlowered (raised for implantation in the upper jaw) until it abuts thejawbone 34 at the gum line 36. The platform 14 is positioned so that itsupper major surface 15 is level with a line or plane at the concernedtooth position. The fastener system 16 is then tightened to secure theplatform 14 to the posts loaded against the jawbone, i.e., the lockwashers and nuts are applied as described above. The core 42 is appliedas described above.

The implantation procedure for a multi-post implant, similar to a singlepost implant, may be carried out during a single visit or multiplevisits depending primarily upon site preparation requirements, e.g.,whether a tooth extraction is involved, and in most instances, can beperformed in a single visit. The dental prosthetic device, a crown 66 bin FIGS. 5-6, is installed as generally described above for the cap 66a.

The embodiment depicted in FIG. 7 includes two dental implants 10 a ofthe type depicted in FIGS. 2 and 5-6 and a bridge prosthetic device 66 cattached to the two implants 10 a. Both implants 10 a are implanted asdescribed in connection with FIGS. 3-6. Impressions for the bridge 66 care taken generally as described above, including down to the gum linesurrounding each platform and the bridged area. A temporary bridge ortwo temporary caps may be installed before the permanent bridge 66 c.Proper positioning places the top of the bridge 66 c in the patient'snormal bite line for the concerned area.

In other embodiments, implants are used to anchor a partial or fullprosthesis extending over a number of tooth positions in the same ordifferent quadrants, etc. The embodiment depicted in FIG. 8 provides aprosthetic device 66 c covering the lower front teeth positions, i.e.,the four incisor teeth and the two adjacent canine teeth. In thisembodiment, four implants 10 are used, to for the two center incisorteeth positions and one each for the canine teeth positions. Theembodiment depicted in FIG. 9 provides a prosthetic device 66 d, similarto the prosthetic device 66 c shown in FIG. 8, covering the lower frontteeth positions, i.e., the four incisor teeth and the two adjacentcanine teeth. In FIG. 9 embodiment, however, six implants 10 are used,one for each of the incisor teeth positions and canine teeth positions.The implants 10 in the FIGS. 8 and 9 embodiments are similar to theimplants illustrated in FIGS. 1 and 3-4, and are installed as describedabove.

Dental implants 10 and 10 a illustrated in FIGS. 1 and 2 are forprosthetic devices of the fixed type. However, dental implants accordingto embodiments of the invention may also be used for removable dentalprosthetic devices. FIG. 10 illustrates a one post embodiment of adental implant 10 b for a removable prosthetic device, e.g., a cap. In aone-post embodiment, e.g., for insertion at a tooth location formerlyoccupied by a single root tooth (which may be referred to as amini-implant), the dental implant comprises at least one post 12 a, anda stabilizer 14. The upper portion 26 a of the post 12 a terminates in aball 57. The implant 10 b is similar to the one post implant illustratedin FIGS. 1 and 3, except that the fastener system comprises the ball 57which bears against the top surface 15 of the platform 14. The post 12 ais inserted through a stabilizer 14 and threaded to the jawbone, withthe ball 57 bearing against the platform, to secure the post and thestabilizer and to load the stabilizer against the jawbone. The ball 57and the removable implant may be conventional, e.g., the ball 57includes a recess 58 to receive an o-ring 59 within a removableprosthetic device 60 which compresses when the removable prostheticdevice is mounted over the ball to removably attach the prostheticdevice to the post.

In the embodiments described above, the larger surface area provided bythe platform and the loading of the platform against the jawboneprovides a stable and permanent fixed base for single and multiple toothimplants. The use of a relatively thin post or posts can minimize theinvasiveness of the procedure, both at a single root or multiple roottooth location, which can permit immediate loading of fixed prostheticdevices, enhance patient tolerance to the procedure, and reduce healingtime.

Training time for professionals to perform the procedures describe aboveis expected to be relatively short, e.g., about two weeks.

As for implants in general, it is expected that not all patients will becandidates for the implants that embody the invention. However, forsuitable candidates, although patient tolerance and healing with varywith patients, their age, state of health, etc., it is expected that theprocedures for installing implants which embody the invention will bemore easily tolerated and involve shorter healing periods, e.g.,approximately two months.

While the invention has been described and illustrated in connectionwith preferred embodiments, many variations and modifications as will beevident to those skilled in this art may be made without departing fromthe spirit and scope of the invention as defined by the claims, and theinvention is thus not to be limited to the precise details ofmethodology or construction set forth above as such variations andmodifications are intended to be included within the scope of theinvention as defined by the claims.

1. A dental implant adapted to be installed in a mouth on a permanentbasis, comprising: at least one post which includes a screw threadextending along at least a portion thereof, each post being adapted tobe secured in a mouth to a jawbone using the screw thread with an endthereof generally facing an opposing jawbone, each post having adiameter within the range of 1.6 mm to 3.7 mm; a stabilizer including ahole therein for each post of the dental implant, the stabilizer beingadapted to support a prosthetic device replacing at least one tooth at ain the mouth in which the implant is to be installed, and to contact thejawbone at that location along a portion of the jawbone that faces theopposed jawbone: a fastener system which in cooperation with the atleast one post is adapted to engage the stabilizer and load thestabilizer against the jawbone in contact therewith along the portionthereof that faces the opposed jawbone
 2. A dental implant adapted to beinstalled in a mouth on a permanent basis, comprising: at least twoposts each of which includes a screw thread extending along at least aportion thereof, each of the posts being adapted to be secured in alocation in the mouth to a jawbone using the screw thread with an endthereof generally facing an opposing jawbone, each post having adiameter within the range of 1.6 mm to 3.7 mm; a stabilizer including ahole therein for each post of the dental implant, the stabilizer beingadapted to support a prosthetic device replacing at least one tooth at alocation in the mouth in which the is to be installed, and to contactthe jawbone at that location along a portion of the jawbone that facesthe opposed jawbpone; a fastener system which in cooperation with the atleast two posts is adapted to engage the stabilizer and load thestabilizer against the jawbone in contact therewith along the portionthereof that faces the opposed jawbones
 3. A dental implant installed ina mouth on a permanent basis, comprising: at least one post whichincludes a screw thread extending along at least a portion thereof, eachpost being secured to a jawbone at least using the screw thread thereofwith an end thereof general1y facing an opposing jawbone, each posthaving a diameter within the range of 1.6 mm to 3.7 mm; a stabilizerincluding a hole therein for each post of the dental implant, thestabilizer being adapted to support a prothetic device replacing atleast one tooth at a location in the mouth in which the implant is to beinstalled, the stabilizer contacting the jawbone at that location alonga portion of the jawbone that faces the opposed jawbone with arespective post in alignment with a respective stabilizer hole; and afastener system which in cooperation with at least one post engages thestabilizer and loads the stabilizer against the jawbone in contacttherewith along the portion thereof that faces the opposed jawbone. 4.The dental implant of claim 1, 2 or 3, wherein the stabilizer comprisesa platform including opposed major sides and at least one minor side. 5.The dental implant of claim 4, wherein: the opposed major sides of theplatform are parallel and the at least one minor side is transverse tothe major sides.
 6. The dental implant of claim 1 or 2, wherein eachpost is adapted to extend beyond the stabilizer through a respectivehole therein and the fastener system comprises a threaded nut for eachpost and a complementarily threaded portion of a respective post in theportion thereof adapted to extend beyond the stabilizer.
 7. The dentalimplant of claim 1 or 2, comprising at least one anchor adapted to beattached to the dental implant projecting from the stabilizer andadapted to assist in securing the prosthetic device to the dentalimplant.
 8. The dental implant of claim 1, wherein the dental implant isadapted to be installed at a location in the mouth formerly occupied bya tooth having a single root, and wherein the dental implant comprises asingle post.
 9. The dental implant of claim 3, wherein the dentalimplant is installed at a location in the mouth formerly occupied by atooth having a single root, and wherein the dental implant comprises asingle post.
 10. The dental implant of claim 1 or 2, wherein the dentalimplant is adapted to be installed at a location in the mouth formerlyoccupied by a tooth having two or more roots, and wherein the dentalimplant comprises at least two posts.
 11. The dental implant of claim 3,wherein the dental implant is installed at a location in the mouthformerly occupied by a tooth having two or more roots, and wherein thedental implant comprises at least two posts.
 12. A combination of adental implant according to claim 1, 2 or 3 and a prosthetic deviceadapted to be attached to the implant.
 13. The combination of claim 12,wherein the prosthetic device comprises structure replacing a singletooth.
 14. The combination of claim 12, wherein the prosthetic devicecomprises structure forming part of a multi-tooth replacement.
 15. Thedental implant of claim 1, 2 or 3 wherein the dental implant is adaptedto receive at least part of a fixed prosthetic device.
 16. The dentalimplant of claim 1, 2 or 3 wherein the dental implant is adapted toreceive at least part of a removable prosthetic device.
 17. A method ofinstalling a dental implant in a mouth on a permanent basis, the dentalimplant comprising at least one post having a diameter within the rangeof 1.6 mm to 3.7 mm, a stabilizer with a hole therein for each postadapted to support a prosthetic device replacing at least one tooth at alocation in the mouth in which the implant is to be installed, and afastener system for engaging the stabilizer loaded against and incontact with a jawbone at the location in the mouth in which the implantis to be installed along a portion of the jawbone that faces the opposedjawbone, the method comprising: securing each post to the jawbone withan end thereof generally facing an opposing jawbone; positioning thestabilizer with each ho1e thereof aligned with a respective post and incontact with the jawbone at the location in the mouth in which theimplant is to be installed along the portion of the jawbone that facesthe opposed jawbone; and operating the fastener system to engage thestabilizer and load the stabilizer against the jawbone in contacttherewith along the portion of the jawbone that faces the opposedjawbone.
 18. The method of claim 19, wherein each post as secured to thejawbone includes a portion extending beyond the stabilizer, and whereinthe fastener system comprises a screw thread extending in the portion ofeach post extending beyond the stabilizer and a threaded nut, andwherein operating the fastener system comprises threading a respectivenut to the threaded portion of a respective post extending beyond thestabilizer and torqueing the respective nut to load the stabilizeragainst the jawbone.
 19. The method of claim 17, wherein the step ofpositioning the stabilizer follows the step of securing each post to thejawbone.
 20. The dental implant of claim 3, wherein each post extendsbeyond the stabilizer through a respective hole in the stabilizer andthe fastener system comprises a threaded nut for each post and acomplementarily threaded portion of a respective post extending beyondthe stabilizer.
 21. The dental implant of claim 3, comprising at leastone anchor attached to the dental implant projecting from the stabilizerand adapted to assist in securing the prosthetic device to the dentalimplant.
 22. The dental implant of claim 1, 2 or 3, wherein the dentalimplant is adapted to receive at least part of a prosthetic device. 23.A dental implant adapted to be installed in a mouth on a permanentbasis, comprising: at least one post which includes a screw threadextending along at least a portion of the at least one post, each postbeing adapted to be secured in a mouth to a jawbone using the screwthread with an end thereof generally facing an opposing jawbone, eachpost having a diameter within the range of 1 mm to 4 mm; a stabilizerincluding a hole therein for each post of the dental implant, thestabilizer being adapted to support a prosthetic device replacing atleast one tooth at a location in the mouth in which the implant is to beinstalled, and to contact the jawbone at that location along a portionof the jawbone that faces the opposed jawbone; a fastener system whichin cooperation with the at least one post is adapted to engage thestabilizer and load the stabilizer against the jawbone in contacttherewith along the portion thereof that faces the opposed jawbone.